drm/i915: Exercise request cancellation using a mock selftest

Add a mock selftest to preempt a request and check that we cancel it,
requeue the request and then complete its execution.

v2: Error leaks no more.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20170223074422.4125-13-chris@chris-wilson.co.uk
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

1 files changed, 19 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/selftests/mock_request.c b/drivers/gpu/drm/i915/selftests/mock_request.c
index e23242d1b88a..0e8d2e7f8c70 100644
--- a/drivers/gpu/drm/i915/selftests/mock_request.c
+++ b/drivers/gpu/drm/i915/selftests/mock_request.c
@@ -22,6 +22,7 @@
  *
  */
 
+#include "mock_engine.h"
 #include "mock_request.h"
 
 struct drm_i915_gem_request *
@@ -42,3 +43,21 @@ mock_request(struct intel_engine_cs *engine,
 
 	return &mock->base;
 }
+
+bool mock_cancel_request(struct drm_i915_gem_request *request)
+{
+	struct mock_request *mock = container_of(request, typeof(*mock), base);
+	struct mock_engine *engine =
+		container_of(request->engine, typeof(*engine), base);
+	bool was_queued;
+
+	spin_lock_irq(&engine->hw_lock);
+	was_queued = !list_empty(&mock->link);
+	list_del_init(&mock->link);
+	spin_unlock_irq(&engine->hw_lock);
+
+	if (was_queued)
+		i915_gem_request_unsubmit(request);
+
+	return was_queued;
+}